This application is a 35 U.S.C.§371 national stage filing from International Application No. PCT/CA2008/000099, filed Jan. 18, 2008, which claims priority to Canadian Patent Application Nos. 2596524, filed Aug. 8, 2007, and 2574753, filed Jan. 19, 2007, the teachings of which are incorporated herein by reference.
Ice skates have been used for recreational and transportation purposes for hundreds of years. Originally, some sort of low friction sliding device akin to a metal blade was attached using straps to a conventional boot. Eventually, in the past century, boots specifically intended for use only in ice skating evolved, typically with the blade firmly affixed to the boot. The unitary blade and boot had the advantage of rigidity allowing more speed and control than previously possible.
For many years, it has been realized that there may be an advantage to providing a replaceable sharpened blade for ice skates. With heavy use, typically a conventional skate blade will wear out before the boot portion. Accordingly, there is an advantage to extending the life of the skate by replacing the blade rather than replacing the entire skate.
For advanced skaters particularly, the degree of curvature of the blade (referred to as “rocker” in the industry) is important. Different skaters will choose different rocker curvatures depending upon their personal preferences. Unfortunately, with conventional skate construction, manual sharpening of the skates in which the blade and rocker are synonymous tends to vary the rocker curvature slightly. Over the course of the lifetime of a conventional skate, this curvature can vary dramatically.
In addition, sharpening must normally be done by someone other than the skater using special grinding equipment. This is often inconvenient to the skater and involves a certain expense.
Certain of the prior art attempts to provide replaceable skate blades have involved replacement of a relatively heavy, and thus expensive, metal portion of the skate with substantial removal and fastening difficulties. Some such replaceable blades were intended to be sharpened a number of times before replacement. See, for example U.S. Pat. No. 5,088,749 to Olivieri. In other prior art attempts, the replaceable blade, although lightweight, has not been effectively mounted on the rocker to provide the security required particularly by advanced skaters. See, for example, U.S. Pat. No. 2,108,128 to Kinney. Still other replacement blades have been of a complex construction not easily adapted to inexpensive commercial production. See, for example, German Patent No. 724488 to Dornseif and U.S. Pat. No. 3,947,050 to Isely. Moreover, replaceable blades have tended to be prone to breakage owing to the structure of the blade and the tension under which the blade is placed in order to stretch it along the base of a skate blade. See, for example, U.S. Pat. No. 5,383,674 to Cann, et al.
U.S. Pat. No. 5,988,683 to Venier et al. describes a replaceable blade system in which the shortcomings of the prior art, including the excess breakage associated with the Cann patent configuration, has been solved using a novel means to connect the flexible replaceable blade to the skate so that it is pulled more or less longitudinally and tensioned evenly along its length. A torque limiting device provides for easy replacement and adjustment of blades by consumers without damage to the skate or the replaceable blade. A limitation of this arrangement is that the associated attachment and tensioning mechanism is complex and requires a separate torque limiting tool to operate. An additional problem of the Venier patent is that the tensioning mechanism requires a high stiffness and high strength rigid holder for mounting.
The present invention solves these prior art problems. The skate of the present invention utilizes an identical flexible replaceable blade configuration to the prior art patent of Venier. This blade is inexpensive, light and easily changed and can be replaced with little or no wear on the remainder of the skate. A result of this construction is that the blade is evenly tensioned along its length and the rocker curvature will not vary since no manual sharpening is required. In addition, different rocker curvatures can be chosen according to the user's preference and the identical replaceable blade can be used with all such rocker curvatures. The configuration of the present invention differs from the Venier prior art in that a pivoting rocker section is utilized to connect the blade to the skate. This pivoting rocker section utilizes differential radiuses to tension the blade once it has been retained rather than the tensioning bolt, tension plate and torque limiting mechanism of the Venier patent.
A simple retention latch is configured to retain the pivoting rocker section in a closed position with the flexible replaceable blade held in tension. The retention latch can be simply operated by a skater to release the pivoting rocker section to a released position for blade replacement. This system is superior to the Venier arrangement in that it does not require a separate tool to operate, the tensioning loads are contained within the rocker so the holder can be constructed from regular plastic materials and the number of parts and complexity are significantly reduced. Additionally the cross-sectional shape of the rocker of the present invention is significantly simpler than that of the Venier configuration allowing for the use of lower cost manufacturing techniques.
Another advantage of the present invention is that the retention system of the flexible replaceable blade configuration can also be utilized for a single piece solid blade system. The single piece blade system incorporates a blade along its lower surface. The solid blade arrangement can be sharpened in a conventional manner as well as removed and replaced so as to extend the overall life of the ice skate assembly.